All I can add to the splendid info you already have, is that Kihon Dosa will help you as a beginner to form the FOUNDATION of most of your techniques. They are exercises that, as said before, will help you to maintain your centre, posture etc. while doing certain techniques later on.

Upon investigation, you may realise that one of the Kihon Dosa forms are actually the beginnings of the technique called Shi ho nage. This is how Kihon Dosa works it allows a beginner to practice movements that can be later translated into actual techniques.

I am by no means an authority on Yoshinkan style Aikido, but I've done a bit of it to develop self defence variations to the Shodokan style that I do. I hope this is of help.